When you use console.log(), console.warn(), or console.error() in a webview, these messages appear in the developer tools console for that webview. They do not appear in the VS Code Output panel by default. To view these logs:

Open the Command Palette (Ctrl+Shift+P or Cmd+Shift+P) Type and select "Developer: Open Webview Developer Tools" In the developer tools window that opens, go to the Console tab